AU2002331885A1

AU2002331885A1 - Crystalline forms of ertapenem sodium

Info

Publication number: AU2002331885A1
Application number: AU2002331885A
Authority: AU
Inventors: Karel M. J. Brands; Louis S. Crocker; Raymond Cvetovich; Elizabeth S. Fisher; Ronald Jobson; Amar J. Mahajan; Charles Orella; Daniel R. Sidler; Michael D. Ward; Robert M. Wenslow; John M. Williams
Original assignee: Merck and Co Inc
Current assignee: Merck and Co Inc
Priority date: 2001-09-26
Filing date: 2002-09-20
Publication date: 2003-06-26
Anticipated expiration: 2022-09-20

Description

TITLE OF THE INVENTION

CRYSTALLINE FORMS OF CARBAPENEM ANTIBIOTICS AND METHODS

OF PREPARATION

BACKGROUND OF THE INVENTION

Carbapenems are a broad class of antibiotic compounds useful for the treatment of infectious diseases, including gram positive and negative, aerobic and anaerobic bacteria. U.S. Patent No. 5,478,820 to Betts et al, issued December 26, 1995, now assigned to Zeneca Ltd. (incorporated herein by reference thereto), teaches carbapenem compounds, salts and hydrolysable esters thereof, of the general formula I:

I wherein R¹ is 1-hydroxyethyl, 1-fluoroethyl or hydroxymethyl, R² and R³ are hydrogen or C alkyl, and R⁴ and R⁵ are hydrogen, halo, cyano, nitro, hydroxy, alkylamino, aminosulphonyl, or carbamoyl.

Crystalline forms of carbapenem antibiotics are desirable for improved purity and stability compared with amorphous forms. Crystallization allows isolation of a compound with rejection of impurities, and crystalline forms tend to be more stable than amorphous forms of the same compound. In the present invention, crystalline forms of the carbapenem (4R,5S,6S,8R,2'S,4'S)-3-[[2-[[(3-carboxyphenyl) amino]carbonyl]pyrrolidin-4-yl]thio]-4-methyl-6-(l-hydroxyethyl)-7-oxol-azabicyclo [3.2.0}hept-2-en-2-carboxylic acid have been discovered and characterized and the processes for making said forms are disclosed.

The compounds of formula I can generally be synthesized taking into account the disclosure of U. S. Patent Nos., 6063931 granted May 16, 2000, 5,648,501 granted July 15, 1997, 5,478,820 granted December 26, 1995, 6,180,783 granted January 30, 2001, 5,872,250 granted February 16, 1999 and 5,965,747, granted October 12, 1999 (all incorporated herein by reference). See also Bugay, D.E., Pharm. Res., 1993, 10, 317; Harris, R.K., et al., Spectrochimica Acta, 1989, 45A, 465; Byrn, S.R., et al., J. Pharmaceutical Sciences, 1985, 74, 565.

SUMMARY OF INVENTION

Crystalline forms of the carbapenem (4R,5S,6S,8R,2'S,4'S)-3-[[2-[[(3- carboxyphenyl)amino]carbonyl]pyrrolidin-4-yl]thio]-4-methyl-6-(l-hydroxyethyl)-7- oxol-azabicyclo[3.2.0]hept-2-en-2-carboxylic acid (formula II) and processes for making said forms are disclosed:

II

Specifically, crystalline forms, which are solvates and hydrates or mixed solvates/hydrates of the monosodium salt Ila, are disclosed. These crystalline forms are useful in the isolation and purification of the carbapenem of formula Ha in the manufacture of an antibiotic product for the treatment of serious infections.

Ila

BRIEF DESCRIPTION OF THE DRAWINGS

The invention is described in connection with the following figures, of which:

Figure 1 is the X-Ray Powder Diffraction pattern of Compound Ha crystallized from a mixture of water, methanol, and 1-propanol. Figure 2 is the solid-state NMR spectrum of Compound Ha crystallized from a mixture of water, methanol, and 1-propanol.

Figure 3 is the X-Ray Powder Diffraction pattern of Compound Ha after contacting 2-propanol containing 15% water. Figure 4 is the solid-state NMR spectrum of Compound Ha after contacting 2-propanol containing 15% water.

DETAILED DESCRIPTION OF THE INVENTION

A carbapenem of formula I can be prepared according to several methods known in the art. Generally, these carbapenems can be prepared according to U.S. Patent No. 4,888,344 to M. Sunagawa, issued December 19, 1989, as well as

U.S. Patent No. 4,943,569 to M. Sunagawa, issued July 24, 1990, as well as U.S.

Patent No. 5,478,820 to Betts et al, issued December 26, 1995, all incorporated herein by reference thereto. Additional starting compounds and methods of preparation are taught in 5,641,770 to Kwak et al., issued June 24, 1997 and

5,756,765 to Kwak et al., issued May 26, 1998, incorporated herein by reference hereto.

The compound having the structural formula II:

II

can be isolated by crystallization as the monosodium salt which is represented by the structural formula Ila:

Ila The crystalline forms of this invention are not thermally stable and do not exhibit distinct, well-defined melting points, but rather undergo decomposition upon heating. The compound of formula Ila readily converts from one crystalline form to another or from amorphous material to a crystalline form depending upon the composition of the solvent that the compound contacts. In addition to the crystalline forms derived by crystallization, crystalline forms of the compound of formula Ha arising by contact of the compound with mixtures of water and certain alcohols are also disclosed herein. These forms are useful in maintaining crystallinity through washing operations intended to remove impurities and in producing seed that can be used to improve performance of the crystallization.

The crystalline compound of formula Ila losses crystallinity thereby producing amorphous material under dehydrating conditions as when the solid is contacted by dry gas or dry water miscible solvent such as ethanol each of which can result in reducing the water content of the solid to less than about 13%, correcting for residual organic solvent.

The crystalline solids are characterized below by virtue of their X-Ray Powder Diffraction (XRPD) patterns and solid-state nuclear magnetic resonance (NMR) spectra, which are useful in unambiguous identification of the unique forms disclosed herein. The XRPD patterns were collected on a Philips automated powder diffractometer with XRG 3100 control and PW3710 mpd control using CuKα radiation with an accelerating potential of 45 kV and a filament emission of 40 mA. Diffraction patterns were collected from about 2 to about 40 °2Theta. The solid-state NMR spectra were generated using a Bruker DSX 400WB NMR system operating a 100.6 MHz for ¹³C and 400.1 MHz for 1H using a Bruker MAS 400WB BL7 double- resonance probe with a spinning module housing a 7 mm zirconia rotor with either KEL-F® end caps with a liquid seal plug or zirconia endcaps. The solid-state ¹³C NMR spectra were acquired using cross polarization (CP), magic-angle spinning (MAS), and high-power decoupling. Proton and carbon 90° pulse widths were ~4 μsec with a contact time of 2.0 msec. The sample was spun at 7.0 kHz and a total of 600-800 scans were collected with a recycle delay of 7.0 sec. Sample temperature between -20 and -5 °C. A line broadening of 10 Hz was applied before FT was performed. Chemical shifts are reported on the TMS scale using the carbonyl carbon of glycine (176.03) as a secondary reference.

Form A:

The crystalline Form A is formed through crystallization from a solution containing a compound of formula Ila or by contact of a solid of formula Ha with a mixture of water, methanol, and 1-propanol. This form is unambiguously characterized as having the XRPD pattern 18.44, 13.09, 8.43, 7.58, 6.48, 6.16, 5.55, 5.14, 4.81, 4.50, 4.26, 4.11, 4.02, 3.85, 3.69, 3.41, 3.35, 3.03, 3.25, 3.12, and 2.87 angstroms. More complete XRPD data pertaining to the compound is shown below in Table 1.

TABLE 1. XRPD pattern for the compound of formula Ha (Form A) crystallized from a mixture of water, methanol, and 1-propanol.

The XRPD pattern corresponding to Table 1 is shown in Figure 1. The solid-state NMR pattern corresponding to Form A is shown in Figure 2.

Form B:

The crystalline Form B of the compound of formula Ha is formed through contact of the compound of formula Ila with a mixture of water and 2- propanol and is unambiguously characterized as having the XRPD pattern 18.48, 13.02, 11.27, 8.50, 7.51, 6.51, 6.13, 5.82, 5.13, 4.78, 4.67, 4.50, 4.24, 4.06, 3.85, 3.69, 3.63, 3.41, 3.36, 3.31, 3.22, 3.11, 2.98, 2.87, and 2.77 angstroms. More complete XRPD data pertaining to the compound is shown below in Table 2.

TABLE 2. XRPD pattern for the compound of formula Ila (Form B) contacted with a

The XRPD pattern corresponding to Table 1 is shown in Figure 3. The solid-state NMR pattern corresponding to Form B is shown in Figure 4.

This invention also relates to a process for producing a crystalline carbapenem salt of formula Ila:

πa comprising adding about 10 to 30% of an organic solvent including but not limited to Ci to C₅ alcohols to an aqueous solution containing a compound of formula II, its carbamate form (e.g., structural formula 4) and/or salt forms thereof, cooling the resulting solution to below -5 °C, adjusting the pH using a solution of an acid such as formic acid, acetic acid, propionic acid, or hydrochloric acid, preferably acetic acid, in an organic solvent including but not limited to Ci to C₄ alcohols, preferably methanol, to give the pH required for crystallization of the compound of formula Ila (pH of about 5 to about 6). The solution is seeded with a slurry containing Compound Ha (up to about 0.5% relative to Compound Ha going into the crystallization) in a mixture of water, methanol, and 1-propanol (10-30, 5-15, and 3-7 mlJg of Compound Ila charged to make the slurry, respectively). The carbamate form of the compound of formula II is formed at the pyrrolidinone nitrogen.

The compound is crystallized by adding from 0.5 to 2 volumes of methanol relative to the aqueous volume, and a C₂.₅ alcohol (from 0.5 to 2.5 volumes relative to the aqueous volume), preferably 1-propanol, at between -5 and -25°C to give crystalline Form A. The solid is then washed with a mixture of water and 2- propanol (from 5 to 30 mL/g of the compound of formula Ha) with said mixture containing from 5 to 20% water (v/v) to give crystalline Form B.

The crystalline form of formula Ila as crystallized from a solution containing formula Ila in a mixture of water/methanol/1-propanol is also referred to herein as (4R,5S,6S,8R,2'S,4'S)-3-[[2-[[(3-carboxyphenyl)amino]carbonyl]- pyrrolidin-4-yl]thio]-4-methyl-6-(l-hydroxyethyl)-7-oxol-azabicyclo[3.2.0]hept-2- en-2-carboxylic acid monosodium salt.

The crystalline compound of the present invention is used in the manufacture of a drug product that is useful for the treatment of bacterial infections in animal and human subjects.

SCHEME 1

PNB = para-nitrobenzyl J- _

Ila

The crystalline forms can be produced in accordance with the following non-limiting examples. EXAMPLE ONE

A hydrogenator is charged with 63 g of 5% Pd on carbon catalyst (dry weight) in 1.8 L of water. The vessel is placed under hydrogen then vented and placed under nitrogen. Sodium hydroxide (68 g, 50%) is charged adjusting the pH to about 7.5 with carbon dioxide.

The enol phosphate (170 g) and the thiol (86 g) are dissolved in 1.3 L of N-ethylpyrrolidinone (NEP). The mixture is cooled to below -40°C and 1,1,3,3- tetramethylguanidine (109 g) is added. After 3 hours, the reaction mixture is quenched into the hydrogenator at below 15°C adjusting the pH to about 8 with carbon dioxide. The vessel is placed under hydrogen. When the reaction is complete, the hydrogen is vented and the reaction mixture is treated with activated carbon and filtered. The filtrate is extracted with iso-amyl alcohol containing diphenylphosphoric acid (240 g) and 50% NaOH (44 g). The resulting aqueous solution is further extracted with iso-amyl alcohol to give an aqueous solution containing at least 90 mg/mL of the compound of formula II (predominantly in the stabilized form, 4). Both extractions are performed using two CINC (Costner Industries Nevada Corporation) centrifugal separators set in series for countercurrent extraction. 1-Propanol is added (20% by volume) and the resulting solution is cooled to below -5°C. The pH is adjusted to 5.5 at below -5°C using a solution of acetic acid in methanol (3 M). Methanol and 1-propanol are respectively added to 0.5 and 0.25 volumes total relative to the aqueous solution from the extraction. The resulting solution is seeded with a slurry containing 0.1 g of the compound of formula Ha in a mixture of water, methanol, and 1-propanol (2, 1, and 0.5 mL, respectively) prepared at -10 °C. The product is then crystallized at below -5 °C by adding methanol and 1- propanol to bring the total of each to one volume relative to the aqueous solution from the extraction and isolated by filtration to give the compound of formula Ha as a crystalline solid (Form A).

EXAMPLE TWO

The solid derived by crystallization from a mixture of water, methanol, and 1-propanol (Form A) is washed with a mixture of water and 2-propanol (15:85 v/v, 10 mL/assay g of compound Ila) at below 10 °C to give the compound of formula Ila as a crystalline solid (Form B).

Claims

WHAT IS CLAIMED IS:

1. Crystalline (4R,5S,6S,8R,2'S,4'S)-3-[[2-[[(3- carboxyphenyl)amino]carbonyl]pyrrolidin-4-yl]thio]-4-methyl-6-(l-hydroxyethyl)-7- oxol-azabicyclo[3.2.0]hept-2-en-2-carboxylic acid monosodium salt, formula Ha:

Ila

as crystallized from a mixture of water/methanol/1-propanol.

2. Crystalline (4R,5S,6S,8R,2'S,4'S)-3-[[2-[[(3- carboxyphenyl)amino]carbonyl]pyrrolidin-4-yl]thio]-4-methyl-6-(l-hydroxyethyl)-7- oxol-azabicyclo[3.2.0]hept-2-en-2-carboxylic acid monosodium salt, formula Ha, in accordance with claim 1, having an X-ray powder diffraction pattern of Form A in accordance with figure 1.

3. Crystalline (4R,5S,6S,8R,2'S,4'S)-3-[[2-[[(3- carboxyphenyl)amino]carbonyl]pyrrolidin-4-yl]thio]-4-methyl-6-(l-hydroxyethyl)-7- oxol-azabicyclo[3.2.0]hept-2-en-2-carboxylic acid monosodium salt, formula Ha, in accordance with claim 1, having an X-ray powder diffraction pattern 18.44, 13.09, 8.43, 7.58, 6.48, 6.16, 5.55, 5.14, 4.81, 4.50, 4.26, 4.11, 4.02, 3.85, 3.69, 3.41, 3.35, 3.03, 3.25, 3.12, and 2.87 angstroms of Form A:

4. Crystalline (4R,5S,6S,8R,2'S,4'S)-3-[[2-[[(3- carboxyphenyl)amino]carbonyl]pyrrolidin-4-yl]thio]-4-methyl-6-(l-hydroxyethyl)-7- oxol-azabicyclo[3.2.0]hept-2-en-2-carboxylic acid as formed on contacting the compound of formula Ila :

Ila with a mixture of water/2-propanol.

5. Crystalline (4R,5S,6S,8R,2'S,4'S)-3-[[2-[[(3-carboxyphenyl) amino]carbonyl]pyrrolidin-4-yl]thio]-4-methyl-6-(l-hydroxyethyl)-7-oxol- azabicyclo[3.2.0]hept-2-en-2-carboxylic acid monosodium salt, formula Ua, in accordance with claim 4, having an X-ray powder diffraction pattern of Form B in accordance with figure 3.

6. Crystalline (4R,5S,6S,8R,2'S,4'S)-3-[[2-[[(3-carboxyphenyl) amino]carbonyl]pyrrolidin-4-yl]thio]-4-methyl-6-(l-hydroxyethyl)-7-oxol- azabicyclo[3.2.0]hept-2-en-2-carboxylic acid monosodium salt, formula Ha, in accordance with claim 4, having an X-ray powder diffraction pattern 18.48, 13.02, 11.27, 8.50, 7.51, 6.51, 6.13, 5.82, 5.13, 4.78, 4.67, 4.50, 4.24, 4.06, 3.85, 3.69, 3.63, 3.41, 3.36, 3.31, 3.22, 3.11, 2.98, 2.87, and 2.77 angstroms of Form B:

7. A process for preparing a crystalline, carbapenem monosodium salt of formula Ila:

comprising the steps of:

a) adding an organic solvent to an aqueous solution containing carbapenems of formula II and 4:

II

Na⁺

and/or salt forms thereof, b) cooling the solution to below -5°C;

c) adjusting the pH to between about 6 and about 5 utilizing an acid;

d) crystallizing by adding to the solution from about 0.5 to about 3.0 volumes of methanol relative to the aqueous solution volume, and, optionally, from about 0.5 to about 3.0 volumes of a Cι-₅ alcohol relative to the aqueous solution volume;

and

e) isolating the formula Ila carbapenem crystals.

8. The process according to Claim 7, wherein the Cι-₅ alcohol is selected from the group consisting of methanol, 1-propanol, 2-propanol, isopropyl alcohol, ethanol, 1-butanol, 2-butanol, isobutyl alcohol, t-butyl alcohol, 1-pentanol, 2- pentanol, 3-pentanol, isopentyl alcohol and mixtures thereof.

9. A process according to claim 7 which is conducted at a temperature of about -5°C to about -25°C and wherein the acid is selected from a group consisting of formic acid, acetic acid, propionic acid, and butyric acid.

10. A process according to claim 9 wherein the acid is acetic acid.

11. A process for preparing a crystalline, carbapenem monosodium salt of formula Ila, Form A:

comprising the steps of:

a) adding 1-propanol to an aqueous solution containing carbapenems of formula II and 4:

II

and/or salt forms thereof,

b) cooling the solution to below -5°C;

c) adjusting the pH to between about 6 and about 5 utilizing an acid;

d) crystallizing by adding to the solution from about 0.5 to about 3.0 volumes of methanol relative to the aqueous volume, and from about 0.5 to about 3.0 volumes of 1-propanol relative to the aqueous solution volume;

and

e) isolating the formula Ha Form A carbapenem crystals.

12. A process according to claim 11 which is conducted at a temperature of about -5°C to about -25°C and wherein the acid is selected from a group consisting of formic acid, acetic acid, propionic acid, and hydrochloric acid.

13. A process according to claim 12 wherein the acid is acetic acid.

14. A process according to claim 12 for preparing a crystalline, carbapenem monosodium salt of general formula Ha, Form B:

Ila, Form B comprising: washing solids containing formula Ila Form A crystals with a mixture of water and 2- propanol to give the compound of formula Ila, Form B, wherein said mixture contains from about 5% to about 25% water (v/v).